


Huh.

by HeavenlyHell



Category: Star vs. The Forces Of Evil
Genre: Demon AU, M/M, Smut in the 2nd Chapter, cause the underworld has not presented enough characters for me to do this, demon!Marco, everybodys friends, not quite sure how im gonna end this but lol im gonna try, some minor oc's to keep the story up, theres a bit of a violent scene but its not much, tomco - Freeform
Language: English
Status: In-Progress
Published: 2016-12-03
Updated: 2016-12-03
Packaged: 2018-09-01 04:08:03
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,766
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/8606782
Author URL: https://archiveofourown.org/users/HeavenlyHell/pseuds/HeavenlyHell
Summary: Tom stared at the icy blue-eyed demon in front of him. The smaller thing was obviously uncomfortable under his scrutinizing gaze, its wings fluttering anxiously. A thin red tail with a spade at the end tapped nervously on the cushions it was seated upon, and curled horns poked their way through messy brown hair. “So... Let me get this straight... A necromancer turned Marco into a demon?”





	

**Author's Note:**

> Low-key sorry high-key not  
> I'm sick ok its me being delusional and Tomco being cute

Tom stared at the icy blue-eyed demon in front of him. The smaller thing was obviously uncomfortable under his scrutinizing gaze, its wings fluttering anxiously. A thin red tail with a spade at the end tapped nervously on the cushions it was seated upon, and curled horns poked their way through messy brown hair. “So... Let me get this straight... A necromancer turned Marco into a demon?”

“Yeah!” Star exclaimed, long blonde hair bouncing at her movements. “We were fighting it, and it zapped Marco out of nowhere, and he started burning up, and he turned into this!“ She held her arms out emphasizing the very much not completely human thing on the bed.

'This,' or Marco, flicked his now pointy ear. “Do you have any clue how to turn me back? Not that being a demon isn’t cool or anything, but I’m not sure I can deal with this for the rest of my life.” Marco’s long thin tail whapped himself on the leg, the thing currently flailing everywhere due to Marco’s unsteady emotions.

Tom crossed his arms, examining Marco’s newfound tan horns. “I may know a mage back underground who knows a thing or two about black magic,” Tom stated, and Marco perked up easily. “But you’d have to see her personally, because as knowledgeable as she may be, a human turning into a demon isn’t exactly a case that’s common. She’ll probably need to examine you before she can help.”

“That’s fine,” Marco eagerly said, wings fluttering again, but this time in excitement. “Anything that’ll help this situation.”

Tom grinned. “Alright. Let’s go to my carriage,” He turned to lead the way.

“WAIT!” Star exclaimed, making both boys jump and turn.

“Star, what’s wrong?” Tom asked quizzically, “Don’t scream like that.”

“I totally forgot I have this family thing back in Mewni that lasts the entire weekend! Marco and I were supposed to go tonight!” Star pulled on her hair, looking to her now demon best friend. “Remember? The Butterfly Family Flyout?”

Marco was poker faced, and Tom opened his mouth. “Well, if you want to go Marco, I can pick you guys up on-“

Marco grabbed Tom and practically dragged him on the demonic elevator, yelling, “TAKE US DOWN.” to the red demon carrying the mechanism.

“Wha- Marco?!” Star hollered, having been left behind.

“Sorry Star, I really want to be a human again, looks like you have to go alone, have fun, tell your parents I said hi!” The large doors of the elevators closed just as Star was about to say something else, and Marco huffed before sitting down across from Tom.

The red haired demon blinked. “What was all that about?”

Marco sighed, tail flicking guiltily. “Ever since Queen Butterfly let Mr. Butterfly do more of his... extreme activities, Star’s dad started this thing sometime last year called the Butterfly Family Flyout, where you get flung into the air and try to fight someone else who also got flung.”

Tom’s three eyes widened. “Sounds fun!” His sharp teeth flashed in a grin.

“The exact opposite!” Marco exclaimed. “It was terrible!” He repressed a shudder as he recalled being chucked into the air much thanks to a demanding Star.

There was a pleasant ding as they arrived in the underworld, and the heavy doors opened to reveal an eerie looking cave. “The mage lives here?” Marco questioned, tilting his head.

“Yep. C’mon,” Tom stated, hopping off, and Marco followed suit.

“Are we just supposed to walk in, or...?” Marco’s new icy eyes trailed the lip of the cavern. Thanks to his new eyes, however, he could see well enough into the cave to realize it wasn’t just a cave. It looked more like a house, with books and herbs hanging from the ceiling.

“Hi, Mage Karnia.” Tom greeted.

“Karnia? Who’s-“ Marco cut himself off as he noticed the short hooded figure next to him. An embarrassing squeak left his lips as he jumped high into the air, surprising Tom, who caught him princess style, careful of Marco’s new wings.

“Woah, Marco, are you okay??” Tom asked, concerned. The mage stayed silent.

Marco took a deep breath, before turning deep red. How manly. “Yeah,” He replied, turning and stopping short at how close he was to Tom’s face. He froze, suddenly very aware at his own arms gripping the three-eyed demon’s tattered shirt, and his windy tail that had wrapped itself around Toms leg. Squeaking yet again, Marco hurriedly shoved himself off of the demon prince, effectively pushing himself into midair and falling flat onto the dusty floor of the underworld.

“Are you okay?” Tom asked as Marco shoved himself off the ground.

“Yeah...” Marco muttered. “I was just surprised...”

Tom glanced at him once more, before gesturing to the offending figure. “This is Mage Karnia, the person I was talking about who may help you with the whole spell thing.” He turned to the lady, bowing a bit. “Hello, Miss Karnia.”

The Mage pulled back her hood, showing a surprisingly human face. “Thomas, my boy, how are you?” She was definitely old, but her face was warm and trusting.

“I’m doing well, and you?” Tom smiled at the woman.

Marco watched intently. He’s never really seen Tom like this. Sure, ever since they started hanging out, Marco was surprised at how mellow the three-eyed demon could be, but now he seemed so... gentle.

“I’m doing just fine, thank you for asking. And your friend?” The woman, Karnia asked.

Tom looked over, creating eye contact, the soft expression stagnant. A chill ran through Marco’s spine, despite the warmth of the underworld. “His name is Marco, and he’s a human.” Tom turned back to the mage, and the winged demon felt himself breathe again. “A necromancer hit him with some of their dark magic, and he’s turned into a demon.”

The lady hummed. “Come with me,” She stated before turning around. The two trailed after, Marco sticking close to Tom’s back as they were lead into the cavern. The light from inside the cave seemed to radiate from crystals embedded into the earth, and it’s bright blue cast was much different from the lights of lava and fire that were common in the underworld. It wasn’t long until they hit a corner which seemed to be some sort of study. “Take a seat, dear,” Karnia offered to Marco a raised rock just about the right height for a chair. It was lightly cushioned, and Marco sat himself down, mindful of his own tail. “Now, I’m going to examine you, okay? Do not be scared, it will not hurt.”

Marco nodded, and the mage brought up her hands. Marco thought she might do something similar to a regular examination back on earth, and quickly looked at Tom, who just stood there, watching. Embarrassed, the brunette opened his mouth to ask for a bit more privacy, but Mage Karnia’s hands suddenly glowed a bright purple before she closed her eyes, and the light made it’s way to cast itself entirely over Marco. Marco froze, panicking a bit as he felt himself slowly get embraced by the light, but before he got too nervous he felt something gently squeeze his tail. Glancing over, he saw that Tom had wrapped his fingers reassuringly around the limb, offering a comforting smile. Marco took a deep breath before smiling back as the light covered his head, creating a purple tinge in his vision. It lasted for another moment, before disappearing completely off his body.

Karnia opened her eyes once again, blinking. “Hmm...” She said, before letting her hands fall down. “Good news, you aren’t completely a demon. You mostly only look like one.”

“Mostly? What does that mean?” Tom asks, before the clearing of a throat is heard. The prince looks down, Marco bright red and avoiding eye contact.

Tom tilts his head, before Marco mutters, “My tail...”

Looking down, Tom realizes he’s still holding the thin appendage, even absentmindedly rubbing its spaded tip with his thumb. Tom flushes as well, turning deep purple, instantly letting go. “My bad, man!”

“It’s cool,” Marco whispers back, looking back at the mage, who’s eyebrows are raised questioningly. “Continue, please...”

Much to his appeal, Karnia does. “I mean that all the parts of him that look human are human, and all the parts that look demonic, well, are just that.”

Marco tilts his head, his wing stretching a bit inquisitively. “Aren’t most demons like that? I mean, Tom is relatively humanoid.”

“Yes, but have you seen other demons? They look more monster than young master Thomas, and that’s because Thomas is of royal blood. I’m sure you don’t know this since you are from the earth dimension, but the more powerful a demon is the more human they look, and generally they are of higher status.” The mage explains, and Tom puffs up a bit at the mention of his position on the underworld’s social latter. “I am to assume you are not a prince?”

Marco shakes his head. “Not at all. But since I still have my humanistic points, I look like one?”

The mage nods. “That is probably a label you should want to prose while you are here. As for your cure...” She tilts her head. “At the least, it’ll take a week to come up with a potion to fix this.”

“A week?!” Marco exclaims, tail wilting. “How am I supposed to go to school like this?” Tom shared a sympathetic look.

“I recommend not leaving,” Karnia interjects, causing the two demons to look at her. “Dark magic is unpredictable, and it would not surprise me if you were to suddenly spurt more demonic characteristics within the time it takes for me to make the potion.” She looks apologetically at the brown haired demon. “It might be unsafe to surround yourself with humans, and it’ll be best if you stay in this dimension so I can reach you at any time.”

Marco is aghast. “I’m staying here? I’ll miss school then,” Marco anxiously flicked his tail.

Tom patted his back, mindful of the red wings. “It looks like you’ll have to endure it.”

“Master Thomas,” Mage Karnia calls, causing the prince to look at her. “I hope you don’t mind keeping him? I have no space here, and I’m sure if dear Marco were to run into any sudden demonic changes, you’d be able to deal with it.”

Tom nodded. “Of course, Mage Karnia.”

Karnia gave a glad expression before leading them both to the mouth of the cavern. “I will be here. Come to me if you have any issues.”

“Thank you so much,” Marco bowed slightly, along with Tom.

“Good luck,” She called, and the two young demons were off.

“So,” Tom started as they made their way to Toms castle. “A week, huh?”

“Oh man,” Marco groans, “I’m gonna miss so much school.”

Tom rolls his eyes. “C’mon, you nerd. Think of it as this: You and me, a supreme sleepover party!”

Marco grins, looking over to his companion. “I suppose so.”

Tom smiles back. “Now, let’s get you out of those clothes!”

Marco lets himself frown. “What’s wrong with my clothes?” He holds his familiar red jacket, a little dusty from earlier, and holes in the back from his wings, but aside from that, was just fine in his opinion.

Tom juts his head out, deadpanning. “Uh, everything. You stick out like a sore thumb! If you’re gonna be seen with me down here, it calls for a major makeover.”

Marco raises his brow. “Like what?”

Tom strokes his chin thoughtfully. “Come with me,” The taller demon says as he grabs Marco by the wrist and leads him into a shop not far away.

The reptilian shop keeper bows as they enter, and Tom wastes no time to sift through the plentiful racks. “What do demons even wear?” Marco asks nervously, eyeing some rather provocative clothing on the wall.

Tom shrugs, intent on his search. “Here,” the demon chucks a ball of clothes at Marco, who catches it with his face. “Put these on.” Before Marco can say anything, the prince floats up and away, boots on fire.

Sighing, the blue-eyed demon trudges over to the changing room. At least these tops that Tom gave him had slits for wings, how thoughtful.

“Uh... Tom?” Marco calls out when he’s done changing. “I don’t think I can wear this.” It’s not that what he’s wearing looks bad, its just that it’s... not quite what he’d wear. Tom had picked out for Marco leather pants a bit too tight for his liking and a deep maroon tee, covered by a black bomber jacket.

“What? Why?” Tom called, and suddenly the curtain was drawn. A less than manly squeak escaped Marco, and he lashes out at the intruder, who was none other than Tom himself. The three-eyed demon caught his arm easily, and eyed Marco up and down, whistling. “It looks fine! I thought I got the wrong sizes.” Tom turned his head to an associate behind him. “Yeah, we’ll get these! Also the boots,” He motioned to the pair in his hand, using his powers to hand a card over, and the skink-like demon nodded their head, taking the card and moving away to complete the transaction. That having been done, Tom turns back to his companion. “You look good!”

“Uh, thanks,” Marco says, although feeling extremely self conscious. “Those boots are for me too?”

Tom nods. “Yeah! You can’t wear your regular shoes with that. They don’t match.”

Marco raised an eyebrow teasingly. “Since when are you a fashionista?”

Tom shoved Marco playfully. “Just put those on, dork.” The skink demon brings back Tom’s black credit card, which the fire demon transported to who-knows-where, along with Marco’s old clothes. Boots on, the two of them stepped back into the street.

Demons littered the street, staring at Marco and bowing under Toms gaze. “So I look like royalty?” Marco asks, trailing behind Tom closely.

Tom hums. “Yeah. Although you’re not very prince-like,” This earns a glare from the brunette. “But people probably think you are some aristocrat. They’ll probably talk about you for a while, ‘cause I don’t really hang out with white-collars.”

Marco nods, just as the castle gates are seen. Two demons with chains attached to their neck stand at the front, and upon seeing Tom, make their way to pull open the heavy gates. The creaky doors open, revealing a vast courtyard and a massive medieval castle. “Whoa...” Marco awes, craning his neck to see the top of the mighty fortress. He’s never seen the castle outside of Tom’s room.

Tom has an easy smile on his face, stepping up. “Let me show you inside,”

The main hall, or as Marco assumed it to be, was impressive. A high raised ceiling was adorned with a (what else) fire chandelier, and two semi-spiraling staircases led the way to the separate wings of the castle. Tom lead Marco to the right, and Marco eyed the tall heavy demon that made their way down.

“Thomas!” A booming voice echoed out, and deep red eyes squinted upon seeing the two.

“Father.” Tom quips, expression much more flat compared to moments earlier.

Father? Marco thinks, before looking back up to the demon before them. Despite his heavy figure, it was obvious now to see the relation between them. He only had two eyes, but bore the same purple hue, although much more saturated, and fiery, red hair that was shaggy and long and mixed itself with a full beard, making it impossible to tell where one ended and the other began. The tall man bore the same bent horns, although his was massive and bearing.

“I was looking for you. Your uncle is coming ‘morrows light, so be sure to ready yourself to greet him.”

Tom rolled his eyes. “Sure, dad.” Marco eased himself behind Tom’s taller figure in attempt to avoid interaction, but his wings were sticking out obviously, and sure enough, the king noticed.

“Oh? Who’s this?” The large voice thundered, and prying eyes found their way around Toms head. “A friend?”

Marco’s ears were pressed flat against his head, tail low and slowly inching its way between his legs. “Hello, your majesty.”

A large grin, showing rather precarious looking teeth flashed, and the king eased his way back up to his intimidating height. “Manners? That’s something I rarely see from young’uns your age. I was prepared to brace myself for attitude like your buddy Thomas here,” The king commented, laughing heartedly. “Alright, I’ll let you two go. Have fun.”

Tom walked away, Marco unhesitatingly following suit, slinking his way around the Kings’ mighty presence. “Sorry about him.” Tom whispered.

“He’s a bit intense,” Marco whispered back, “but he seems like a nice guy.”

Tom shot an unbelieving look. “You may think so, but you have to wait until you see-“

“WHAT?!?” The kings mighty roar rippled through the air, causing Marco to jump. Looking back, he saw the king breathing hard above a servant. The servants head was bowed, obviously apologizing profoundly, but the king appeared to not be having any of it. With a wave of his large hand, the servant was immediately on fire, its scream filling the air. Another servant had popped in, seemingly just to make their way through the room, when the king raised his hand in their direction, causing them to asphyxiate randomly and fall to the ground, randomly clawing at its own neck, strangled noises escaping it’s mouth.

Marco stood, frozen, at the top of the stairs, watching as the demon who, moments ago, had conversed casually with Marco begin killing everything in his path. Tom’s warm hand on his wrist ripped himself from his trance, and he found himself being led down the hall, the horrific scene being left behind them. “...That.” Tom whispered, looking at the ground as he pulled Marco along. “Wait until you see that. Sorry. I understand if you don’t want to stay with me anymore. I can talk to Karnia, see if she can get someone else-“

Marco broke himself from his shut off trance and spoke up, cutting Tom off. “It’s okay.” Tom glanced over, still leading Marco to wherever. Marco offered a friendly look, speaking. “I’ll still stay with you. I’m shit scared though.”

Tom blinked. “Really?” A nod from his companion was the answer, and he slowed his pace, but did not let go of Marco’s wrist. “...My father is an anger Demon. He controls his emotions towards me because I’m his son, of course, but he gets pretty out of hand... Often. It would probably be best if you stuck with me your entire stay here.”

Tom looks at Marco, and the smaller demon cant help but notice how much his friend looks like a kicked puppy. Marco grinned. “Where else would I be?”

Tom smiled back.

Marco felt his heart skip a beat.

Before he could question himself, Tom abruptly stopped at a door. “We’re here!” He pulled Marco into the room, and the winged demon was glad for the familiar setting. The brunette bounded over and leapt onto Tom’s couch, causing said owner to chuckle as Marco practically purred into the plush leather. Marco’s new sharp ears listened as Tom walked over to the mirror, and Tom voiced, “Mirror, call Star Butterfly on mobile,” to which the device replied, “Calling: Star Butterfly,”

A couple of rings and Star’s bright face showed up on the screen. Her hair was a bit ragged, and it appeared she was inside some dark room. “Hey, guys! How was the mage? Where’s Marco?”

Marco called out from behind Tom, “Hey, Star.”

“Marco! Have you been turned back yet? You’re missing out!” Star grinned cheesily at her best friends voice, although he was hard to be seen from behind the sofa.

“I highly doubt I’m missing out on anything,” Marco muttered, but he was drowned out by Tom’s clear reply.

“Star, Marco hasn’t been turned back yet, and he won’t be until a week. The mage says he needs to stay in the underworld for the time being, just so we can keep and eye on him.”

Star raised her eyebrows. “What? Marco skipping school? Unheard of! Blasphemy! You two having a sleepover everyday?!? Unfair!”

Tom chuckled. “You can always visit, Starship.”

“I know that!” Star grinned. “Or, well, even if I couldn’t visit, I would anyways. I’ll come see you guys on my way back to earth from Mewni!”

“Sounds good,” Marco called from his spot.

“Alright. I’ll call you guys laTEEEEERRRRRRR” Star was seen suddenly in the light, and her face was pulled back from heavy wind. The camera was shaky and the feed was cut abruptly.

“Was that... A canon?” Tom asked, pointing to the mirror and looking at Marco. The reply was a shudder, and Tom got his answer. Moving away from the mirror, Tom walked over to where Marco had sprawled himself on the comfy furniture. “I’m assuming this is where you choose to sleep?” A tired murmur escapes the tailed demon on the couch, making Tom laugh once again. “Go change while I get you pillows and blankets. Check my dresser, I may have things for you.” Marco lazily gets up and stumbles over as Tom pulls the aforementioned sheets from some flames and lays them out on the couch.

Marco finishes dressing rather quickly, and heads back to his beloved sofa, which appears to have just been done tidying up by Tom. The small demon yawns at the thought of laying on its plushy goodness, causing Tom to turn around.

“You sound ready to sleep-“ Tom seems to stutter.

Blinking, Marco looks up. The other demon looks like a deer caught in headlights, staring at Marco rigidly. Tilting a tired head, Marco asks, “Tom?” But the other remains unmoving. Marco looks down. He was only wearing what Tom suggested- some old, baggy T-Shirt he had found that he bet Tom never wore and some shorts that barely peeked out the hem of the swallowing clothing that was his top.

Tom seemed to have shaken himself out of whatever stupor he had found himself in, and sputtered, “Here, go to sleep. I’ll bet turning into a demon really drained a lot out of you,”

Marco nodded drowsily. “You can say that again,” he mutters before collapsing on his beloved couch. He doses off immediately, faintly feeling the warmth of a blanket being pulled up onto his figure, and dreams that night of a comforting fire.

**Author's Note:**

> yeaaahhh  
> like I said not sure how im gonna end this  
> but ill try dammit  
> also  
> haha  
> here I wanted to draw demon marco  
> cuz marco is a qt  
> 


End file.
